Can you find out the missing number in the grid?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

Four cars come to a four-way stop, each coming from a different direction. They can’t decide who got there first, so they all go forward at the same time. All 4 cars go, but none crash into each other. How is this possible?

On a charity event in Russia, Murray beat Djokovic by winning six games and losing three games.
Note: There is a total of 5 service breaks(one who serve lost the game).
Who served first, Djokovic or Murray?

What can go up a chimney down, but can’t go down a chimney up?

How can you spell "White of an egg" in one word?
Hint: I know you can spell coke, poke, and joke.

A little girl goes to the store and buys one dozen eggs. As she is going home, all but three break. How many eggs are left unbroken?

This puzzle is for Harry Potter fans. Do you know why Tom Riddle is called Lord Voldemort?

Solve the mathematical equation in the picture below.

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?